This paper is concerned with theoretical and experimental analysis
of deep plastic collapse of a deck or deep girder subjected to an
in-plane, concentrated load. A theory is derived which is valid
until initition of fracture in the structure. The presented
experimental results show load-deflection curves and modes of
deformation for decks, stringer decks and deep thin-walled beams
subjected to central or excentric point loads between transverse
frames. Based on theory and experiments, various modelling aspects
of the local/global failure of the beams are discussed. The
agreement between the theoretical closed form solutions and the
experimental results is good.